AbstractIn this retrospective case series and literature review, we demonstrate that temporal bone lesions that obstruct the endolymphatic sac or duct can cause symptoms of Ménière's disease. This finding is likely attributable to endolymphatic hydrops; initially, such cases typically masquerade as Ménière's disease. Between July 1995 and April 2002, a total of 379 patients were treated for an initial diagnosis of Ménière's disease at our institution. Among this group, 3 patients were found to have an obstructing lesion of the endolymphatic sac or duct that we felt was causally related to their Ménière's-like symptomatology. We reviewed these cases and noted the similarities in each patient's presentation, including a common pathophysiology. On imaging studies, each patient had a different pathologic lesion that involved the endolymphatic sac or duct: patient 1 had a jugular megabulb, and she was ultimately treated with vestibular nerve section; patient 2 had a cholesterol granuloma, which was treated with surgical excision; patient 3 had an endolymphatic sac tumor that was treated with surgical excision. As has been suggested in previous reports, not all cases of Ménière's disease are idiopathic. We conclude that obstruction of the endolymphatic sac or vestibular aqueduct by a mass lesion or vascular anomaly can lead to vestibulocochlear pathology that mimics Ménière's disease.